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Topic: What darkness level to see Milky Way? (Read 1243 times)

Everyone should see the Milky Way from a truly dark sky at least once. I am at a Bortle 2 to 3 site and it is still worth going to an even darker location. Just because you can "see" the MW at a red or green site does not mean you are truly experiencing the MW.

Yeah, I get the feeling that no matter how dark your views are you want darker. We were up in North Georgia the other day in a bright yellow zone and I was asking the guy at the pumpkin farm if he could recommend a park or something nearby to set up a telescope and he told me that it used to be dark around there, but it wasn't any good anymore.

In our minds, a yellow zone is darker than anywhere we usually get to see and a real treat. To him, this was at best the normal level of darkness but mostly he just remembers it being darker when he was growing up.

I barely managed to see it in a yellow zone, Stellafane is a dark yellow/green zone, and it's spectacular there.

The Milky Way as seen from Stellafane would indeed seem very impressive to anyone coming from any urban area just outside the east coast megalopolis. However, the fact is that from Stellafane the view in the region toward the galaxy's hub is impacted by the combined and compounded light pollution of the highly populated Connecticut River Valley beginning just 20-25 miles south of the convention's site and stretching roughly 150 miles beyond all the way to the shores of the Long Island Sound. I can fully attest to it having been far darker at Stellafane back in the 1960's and 70's.

I might add that from a Dark Sky Scale location with a rating of class 1, essentially as dark as it can get, the Milky Way ismuch more impressive to see and quite literally awe inspiring! From such a site the Milky Way has a distinctly "clumpy" appearance over nearly its entire length from northern Cygnus to the southern horizon. At the same time to the naked eye the Scutum/Sagittarius region is clearly dotted with numerous little condensations that mark Messier objects and a host of other features one sees only with binoculars or a telescope in less favorable locations..BrooksObs

I have barely made out the winter milky way stretching from Capella through Sirius under very clear skies in an orange zone stretching over into a yellow zone. It is not the splendor it is in darker skies, but the question is what is the darkness level required to see it.

In my view, this would be the absolute minimum and only if conditions are nearly perfect. The summer milky way is obscured by cloud most of the year, I don't often get to see the Sagittarius region it unless very early or very late and staying up late in the dry season.

But, that's been my experience, and not often are conditions good enough to barely see it. But, sometimes they are.

Asbytec, your situation in the Philippines really is quite different from what is encountered across much of the United States. In checking the light pollution map for your location in Pampanga I find that travelling a mere dozen miles or so in any direction, other than directly north, or south, puts you into very dark skies. So, although your home may be near the edge of a orange to yellow zone, it is not surrounded by a vast sea of lights beyond extending all the way to the horizon, as most densely populated places in the U.S. are. Here the transitions from one zone to the next extends for scores of miles and there is still much lighting beyond that.

Thus, even though overhead you may have orange-yellow zone skies according the the map, looking in most directions this situation lasts only a few miles and is then backed up by much darker skies. Little wonder then that you can weakly see the winter Milky Way (which is much fainter than the summer portion) on really good clear nights. This would not be possible in the majority of urban American settings from an orange-yellow zone.

BrooksObs, yes, thank you for confirming what I suspected to be true. I can drive three blocks and be in a yellow zone.

Another difference here is the rather accidental shielding of fluorescent bulbs used as street lights. I am grateful they never put in mercury vapor or high pressure sodium in our subdivision. The streets, looking down them, can be quite dark with direct glare being the biggest problem and easiest to shield from. Thankfully. I say accidental shielding because surely the covers they used did not have light pollution in mind. Rather, they are protection from the rain and quite effective shielding for both.

Yes, it does appear that even though LP maps put me at the edge of an orange zone, we're not smack dab in the middle of one and the lighting situation is different. If the winter milky way is still hard to see, then maybe it is more difficult for more modern lighting conditions than do not exist here. Great point and thank you for the comparison.

This light of ours, bouncing around, messing up the night... I take comfort in the fact that an ultra dark site still is lit with the glow of the sky, the star light of the Milky Way, or a solar maximum. There is shadows regardless.